# Rotation Problem, I'm confused on this one

• PremedBeauty
In summary, the problem involves particles with a total mass of 0.0100kg that are glued to a rod of length 6.00cm and negligible mass. The assembly can rotate around a perpendicular axis through point O at one end. The question involves determining the work required to change the rotational rate from 0-20.0 rad/s, from 20.0 rad/s to 40.0 rad/s, and from 40.0 rad/s to 60.0 rad/s. Additionally, the problem asks for the slope of a plot of the assembly's kinetic energy in joules versus the square of its rotational rate (in radians-squared per second squared). To solve the problem, one must consider the
PremedBeauty
.0100kg particles have been glued to a rod of Length L=6.00cm and negligible mass and can rotate around a perpendicular axis through point O at one end. How much work is required to change the rotational rate (a) from 0-20.0 rad/s, (b) from 20.0 rad/s to 40.0 rad/s, and (c) from 40.0 rad/s to 60 rad/s? (d) what is the slope of a plot of the assembly's kinetic energy in joules versus the square of its rotational rate (in radians-squared per second squared)?

----->The question in my mind is the rotation. Is the mass rotating about O? Or is it rotating around the rod? You have to figure the moment of inertia. The radius of the rod is not given, if the rod is rotating on its axis. And, the total mass is not given "0.0100kg particles" is all that is mentioned. I've been working on this problem for hours and don't understand how to finish it and it
s due tomorrow and I have so much left to do in my other classes

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Cannot yet see your diagram so I do not know where the masses are or how many. The problem says it is rotating about a perpendicular axis- that means perpendicular to the length of the rod.

The diagram is on now, it just takes alittle while to load.

PremedBeauty said:
The diagram is on now, it just takes alittle while to load.

Unfortunately it is not on.

Set up the work-energy theorem!

## 1. What is a rotation problem?

A rotation problem is a type of problem that involves rotating an object or shape around a fixed point or axis. It often requires knowledge of geometry and trigonometry to solve.

## 2. How do I know when to use rotation in a problem?

If you come across a problem that involves an object or shape moving in a circular or spinning motion, you may need to use rotation to solve it. Look for keywords such as "rotate," "spin," or "revolve."

## 3. What are the key concepts to understand in rotation problems?

The key concepts in rotation problems include understanding how angles and degrees relate to rotations, the concept of radians, and how to use trigonometric functions to solve for unknown variables.

## 4. How can I visualize rotations to better understand the problem?

One way to visualize rotations is by using a coordinate plane and graphing the original shape, then rotating it to its new position. You can also use physical objects such as a ruler or protractor to physically rotate and measure angles.

## 5. What strategies can I use to solve rotation problems?

Some strategies for solving rotation problems include breaking down the problem into smaller steps, using formulas and equations specific to rotation, and using visual aids such as diagrams or graphs. It may also be helpful to practice with different types of rotation problems to become more familiar with the concepts.

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